The contents of the header <cstdalign> are the same as the C
standard library header <stdalign.h>, with the following changes:
The header <cstdalign> and the header <stdalign.h> shall not
define a macro named alignas.

The contents of the header <cstdbool> are the same as the C
standard library header <stdbool.h>, with the following changes:
The header <cstdbool> and the header <stdbool.h> shall not
define macros named bool, true, or false.